Pen stand



FIG. 1 is a perspective view of pen stand showing my new design;

FIG. 2 is a front elevational view thereof; with the rear side being a mirror image of that shown;

FIG. 3 is a left side elevational view thereof; with the right side being a mirror image of that shown;

FIG. 4 is a top side elevational view thereof; and

FIG. 5 is a bottom side elevational view thereof; and,

FIG. 6 is a second perspective view thereof, the pen depicted by means of broken lines being shown for illustrative purposes only and forming no part of the claimed design. 

The ornamental design for a pen stand, as shown and described. 